1. Field of the Invention
This invention relates to an electrode for electrolysis of water and more particularly to a porous electrode having a catalytic coating for improving the efficiency of the electrolysis.
2. Description of the Prior Art
Many electrodes and processes for their preparation have been developed in the area of fuel cell technology. Such electrodes are described in, for example, Berger, C., Handbook of Fuel Cell Technology, Prentice Hall, 1968, pp. 401-406, and Cairns, E. J. Liebhalfsky, Fuel Cells and Fuel Batteries, John Wiley & Sons, 1968, pp. 289-294. Since the zones for the various reactions occurring in fuel cells must be carefully separated and accurately defined these fuel cell electrodes have multiple layers and require special treatment in their preparation.
Fuel cell electrodes of the above types are unnecessarily complicated for electrolysis of water, and, moreover, the preparation of such electrodes is, in general, too expensive. These deficiencies are especially disadvantageous when the methods are to be used in making large industrial apparatus for the economical preparation of hydrogen.
Electrodes for cells used in electrolysis of water have already been described, for example, in U.S. Pat. 4,039,409. These are generally doped with a catalyst to accelerate the electrochemical reaction.
However, the known electrodes leave something to be desired in their electrical and mechanical properties, and the same is true regarding the catalysts which have been used.
Hence a need has continued to exist for an electrode suitable for electrolysis of water which is efficient and can be manufactured by a simple and economical process.